The soluble guanylate cyclase stimulator IWP‐550 inhibits neuroinflammation
            in vitro
            and
            in vivo

Although inhaled NO (iNO) therapy is often effective in treating infants with persistent pulmonary hypertension of the newborn (PPHN), up to 40% of patients fail to respond, which may be partly due to abnormal expression and function of soluble guanylate cyclase (sGC). To determine whether altered sGC expression or activity due to oxidized sGC contributes to high pulmonary vascular resistance (PVR) and poor NO responsiveness, we studied the effects of cinaciguat (BAY 58-2667), an sGC activator, on pulmonary artery smooth muscle cells (PASMC) from normal fetal sheep and sheep exposed to chronic intrauterine pulmonary hypertension (i.e., PPHN). We found increased sGC α1- and β1-subunit protein expression but lower basal cGMP levels in PPHN PASMC compared with normal PASMC. To determine the effects of cinaciguat and NO after sGC oxidation in vitro, we measured cGMP production by normal and PPHN PASMC treated with cinaciguat and the NO donor, sodium nitroprusside (SNP), before and after exposure to 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, an sGC oxidizer), hyperoxia (fraction of inspired oxygen 0.50), or hydrogen peroxide (H2O2). After treatment with ODQ, SNP-induced cGMP generation was markedly reduced but the effects of cinaciguat were increased by 14- and 64-fold in PPHN fetal PASMC, respectively ( P < 0.01 vs. controls). Hyperoxia or H2O2enhanced cGMP production by cinaciguat but not SNP in PASMC. To determine the hemodynamic effects of cinaciguat in vivo, we compared serial responses to cinaciguat and ACh in fetal lambs after ductus arteriosus ligation. In contrast with the impaired vasodilator response to ACh, cinaciguat-induced pulmonary vasodilation was significantly increased. After birth, cinaciguat caused a significantly greater fall in PVR than either 100% oxygen, iNO, or ACh. We conclude that cinaciguat causes more potent pulmonary vasodilation than iNO in experimental PPHN. We speculate that increased NO-insensitive sGC may contribute to the pathogenesis of PPHN, and cinaciguat may provide a novel treatment of severe pulmonary hypertension.

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Probing the Molecular Mechanism of Human Soluble Guanylate Cyclase Activation by NO in vitro and in vivo

Scientific Reports ◽

10.1038/srep43112 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 9

Author(s):

Jie Pan ◽

Hong Yuan ◽

Xiaoxue Zhang ◽

Huijuan Zhang ◽

Qiming Xu ◽

...

Keyword(s):

Molecular Mechanism ◽

Guanylate Cyclase ◽

Soluble Guanylate Cyclase ◽

Cyclase Activation ◽

Human Soluble Guanylate Cyclase ◽

Guanylate Cyclase Activation

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Nitrite-dependent vasodilation is facilitated by hypoxia and is independent of known NO-generating nitrite reductase activities

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01298.2006 ◽

2007 ◽

Vol 292 (6) ◽

pp. H3072-H3078 ◽

Cited By ~ 78

Author(s):

Thomas Dalsgaard ◽

Ulf Simonsen ◽

Angela Fago

Keyword(s):

Xanthine Oxidase ◽

Guanylate Cyclase ◽

Nitrite Reductase ◽

Soluble Guanylate Cyclase ◽

Nitrite Concentration ◽

Inositol Hexaphosphate ◽

Relative Contribution ◽

Norepinephrine Concentration

The reduction of circulating nitrite to nitric oxide (NO) has emerged as an important physiological reaction aimed to increase vasodilation during tissue hypoxia. Although hemoglobin, xanthine oxidase, endothelial NO synthase, and the bc1 complex of the mitochondria are known to reduce nitrite anaerobically in vitro, their relative contribution to the hypoxic vasodilatory response has remained unsolved. Using a wire myograph, we have investigated how the nitrite-dependent vasodilation in rat aortic rings is controlled by oxygen tension, norepinephrine concentration, soluble guanylate cyclase (the target for vasoactive NO), and known nitrite reductase activities under hypoxia. Vasodilation followed overall first-order dependency on nitrite concentration and, at low oxygenation and norepinephrine levels, was induced by low-nitrite concentrations, comparable to those found in vivo. The vasoactive effect of nitrite during hypoxia was abolished on inhibition of soluble guanylate cyclase and was unaffected by removal of the endothelium or by inhibition of xanthine oxidase and of the mitochondrial bc1 complex. In the presence of hemoglobin and inositol hexaphosphate (which increases the fraction of deoxygenated heme), the effect of nitrite was not different from that observed with inositol hexaphosphate alone, indicating that under the conditions investigated here deoxygenated hemoglobin did not enhance nitrite vasoactivity. Together, our results indicate that the mechanism for nitrite vasorelaxation is largely intrinsic to the vessel and that under hypoxia physiological nitrite concentrations are sufficient to induce NO-mediated vasodilation independently of the nitrite reductase activities investigated here. Possible reaction mechanisms for nitrite vasoactivity, including formation of S-nitrosothiols within the arterial smooth muscle, are discussed.

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Pharmacokinetic interaction profile of riociguat, a new soluble guanylate cyclase stimulator, in vitro

Pulmonary Pharmacology & Therapeutics ◽

10.1016/j.pupt.2014.02.004 ◽

2014 ◽

Vol 28 (2) ◽

pp. 130-137 ◽

Cited By ~ 13

Author(s):

Verena Rickert ◽

Walter Emil Haefeli ◽

Johanna Weiss

Keyword(s):

Guanylate Cyclase ◽

Soluble Guanylate Cyclase ◽

Pharmacokinetic Interaction ◽

Soluble Guanylate Cyclase Stimulator

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The G-protein regulator LGN modulates the activity of the NO receptor soluble guanylate cyclase

Biochemical Journal ◽

10.1042/bj20111882 ◽

2012 ◽

Vol 446 (3) ◽

pp. 445-453 ◽

Cited By ~ 11

Author(s):

Swati Chauhan ◽

Filip Jelen ◽

Iraida Sharina ◽

Emil Martin

Keyword(s):

G Protein ◽

Guanylate Cyclase ◽

Soluble Guanylate Cyclase ◽

Direct Interaction ◽

Inhibitory Effect ◽

Hill Coefficient ◽

Activated State ◽

Ic50 Values

sGC (soluble guanylate cyclase) is the main mediator of NO signalling. Biochemical and physiological studies suggest that, besides NO, in vivo regulation of sGC involves direct interaction with other proteins. Using yeast two-hybrid screening, we identified that the multidomain LGN (Leu-Gly-Asn repeat-enriched protein) interacts with both α1 and β1 sGC subunits. LGN and sGC co-localized in the cell cytoplasm, and the LGN–sGC complex was co-immunoprecipitated from cells expressing both proteins and from native tissues. Their interaction requires the N-terminal tetratricopeptide repeats of LGN, but does not require the N-terminal portions of α1 or β1 sGC subunits. Overexpression of LGN decreases the activity of cellular sGC, whereas knockdown of LGN mRNA and protein correlated with increased sGC activity. Although purified LGN interacts directly with purified sGC, the inhibitory effect in vitro is observed only after supplementation of cell lysate to the reaction. Although resting sGC and sGC activated by the stimulator BAY41-2272 have very similar LGN-IC50 values to the NO-stimulated sGC, they have a much higher Hill coefficient, suggesting co-operative binding with respect to LGN in the low-activated state of sGC. AGS3 (activator of G-protein signalling 3), the closest LGN homologue, also inhibits sGC. The interaction of sGC with these scaffolding proteins may expand the cross-talk between NO/cGMP signalling and other cellular pathways and tailor sGC function to specific tissues or signals.

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Lack of pro-arrhythmic potential for the novel soluble guanylate cyclase stimulator vericiguat: results from preclinical studies

European Heart Journal ◽

10.1093/eurheartj/ehab724.0921 ◽

2021 ◽

Vol 42 (Supplement_1) ◽

Author(s):

H Himmel ◽

A Lagrutta ◽

M Voemel ◽

A.P Rupesh ◽

J.P Imredy ◽

...

Keyword(s):

Soluble Guanylate Cyclase ◽

Preclinical Studies ◽

Once Daily ◽

Integrated Risk Assessment ◽

Integrated Risk ◽

Proarrhythmic Risk ◽

Soluble Guanylate Cyclase Stimulator ◽

Glucuronide Metabolite

Abstract Introduction Vericiguat is an orally-administered soluble guanylate cyclase stimulator, developed for the treatment of symptomatic chronic heart failure (HF) in adult patients who have had a previous decompensation event. At the maximum therapeutic dose of 10 mg once daily in patients with HF, the protein-unbound plasma concentrations of vericiguat and its major pharmacologically inactive N-glucuronide metabolite M-1 are approximately 18 nmol/l and 43 nmol/l, respectively. As part of an integrated risk assessment, vericiguat and its M-1 metabolite were characterised electrophysiologically in vivo and in vitro. This was performed according to the International Council for Harmonisation standard S7B guideline and to recent related “best practice” revisions (draft ICH E14/S7B Q&A), being adopted as a result of the Comprehensive In Vitro Proarrhythmia Assay (CIPA) initiative. Purpose To assess the potential for a proarrhythmic risk from vericiguat and its M-1 metabolite in a series of preclinical studies. Methods The potential for proarrhythmic risk was investigated in conscious telemetered dogs and in a series of in vitro electrophysiological studies, including mechanistic ion channel studies, using both generally accepted and CIPA voltage-clamp protocols under conditions simulating normal and diseased physiological states. The ion channels studied were hERG, hNav1.5, hCav1.2, hKvLQT1/minK and hKv4.3. Transfected human embryonic kidney cell lines were used for the hERG, hNav1.5 and hKvLQT1/minK studies; transfected Chinese hamster ovary cell lines were used for the hCav1.2 and hKv4.3 studies. Results In dogs, administration of vericiguat as single oral doses was associated with dose-dependent decreases in arterial blood pressure (consistent with its mode of action) and compensatory increases in heart rate (Table 1). Heart rate-corrected QT (QTc) intervals were not prolonged by vericiguat to a clinically meaningful extent. Neither vericiguat nor its M-1 metabolite inhibited cardiac ion channels (hERG, hNav1.5, hCav1.2, hKvLQT1/minK and hKv4.3) at exposure multiples of >150-fold (Table 2). Conclusion There was no preclinical evidence of proarrhythmic risk from the in vitro (simulating normal and diseased physiological states) and in vivo assessment of vericiguat or its major N-glucuronide metabolite M-1. This integrated risk assessment of non-clinical data supports the conclusion that administration of vericiguat 10 mg once daily in humans is not associated with meaningful QTc prolongation. FUNDunding Acknowledgement Type of funding sources: Private company. Main funding source(s): Funding for this research was provided by Bayer AG, Berlin, Germany and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.

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Discovery of CYR715: A novel carboxylic acid-containing soluble guanylate cyclase stimulator

Bioorganic & Medicinal Chemistry Letters ◽

10.1016/j.bmcl.2021.127886 ◽

2021 ◽

pp. 127886

Author(s):

Glen R. Rennie ◽

Timothy C. Barden ◽

Sylvie G. Bernier ◽

Andrew Carvalho ◽

Renee Deming ◽

...

Keyword(s):

Carboxylic Acid ◽

Guanylate Cyclase ◽

Soluble Guanylate Cyclase ◽

Soluble Guanylate Cyclase Stimulator

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Discovery of the Soluble Guanylate Cyclase Stimulator Vericiguat (BAY 1021189) for the Treatment of Chronic Heart Failure

Journal of Medicinal Chemistry ◽

10.1021/acs.jmedchem.7b00449 ◽

2017 ◽

Vol 60 (12) ◽

pp. 5146-5161 ◽

Cited By ~ 35

Author(s):

Markus Follmann ◽

Jens Ackerstaff ◽

Gorden Redlich ◽

Frank Wunder ◽

Dieter Lang ◽

...

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Guanylate Cyclase ◽

Soluble Guanylate Cyclase ◽

Soluble Guanylate Cyclase Stimulator

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Acute stimulation of the soluble guanylate cyclase does not impact on left ventricular capacitance in normal and hypertrophied porcine hearts in vivo

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00510.2017 ◽

2018 ◽

Vol 315 (3) ◽

pp. H669-H680 ◽

Cited By ~ 5

Author(s):

Alessio Alogna ◽

Michael Schwarzl ◽

Martin Manninger ◽

Nazha Hamdani ◽

Birgit Zirngast ◽

...

Keyword(s):

Guanylate Cyclase ◽

Soluble Guanylate Cyclase ◽

Diastolic Pressure ◽

Aortic Pressure ◽

Left Ventricular ◽

Concentric Hypertrophy ◽

Ventricular Compliance ◽

Left Ventricular Compliance ◽

Stimulation Of

Experimental data indicate that stimulation of the nitric oxide-soluble guanylate cyclase(sGC)-cGMP-PKG pathway can increase left ventricular (LV) capacitance via phosphorylation of the myofilamental protein titin. We aimed to test whether acute pharmacological sGC stimulation with BAY 41-8543 would increase LV capacitance via titin phosphorylation in healthy and deoxycorticosteroneacetate (DOCA)-induced hypertensive pigs. Nine healthy Landrace pigs and 7 pigs with DOCA-induced hypertension and LV concentric hypertrophy were acutely instrumented to measure LV end-diastolic pressure-volume relationships (EDPVRs) at baseline and during intravenous infusion of BAY 41-8543 (1 and 3 μg·kg−1·min−1 for 30 min, respectively). Separately, in seven healthy and six DOCA pigs, transmural LV biopsies were harvested from the beating heart to measure titin phosphorylation during BAY 41-8543 infusion. LV EDPVRs before and during BAY 41-8543 infusion were superimposable in both healthy and DOCA-treated pigs, whereas mean aortic pressure decreased by 20–30 mmHg in both groups. Myocardial titin phosphorylation was unchanged in healthy pigs, but total and site-specific (Pro-Glu-Val-Lys and N2-Bus domains) titin phosphorylation was increased in DOCA-treated pigs. Bicoronary nitroglycerin infusion in healthy pigs ( n = 5) induced a rightward shift of the LV EDPVR, demonstrating the responsiveness of the pathway in this model. Acute systemic sGC stimulation with the sGC stimulator BAY 41-8543 did not recruit an LV preload reserve in both healthy and hypertrophied LV porcine myocardium, although it increased titin phosphorylation in the latter group. Thus, increased titin phosphorylation is not indicative of increased in vivo LV capacitance. NEW & NOTEWORTHY We demonstrate that acute pharmacological stimulation of soluble guanylate cyclase does not increase left ventricular compliance in normal and hypertrophied porcine hearts. Effects of long-term soluble guanylate cyclase stimulation with oral compounds in disease conditions associated with lowered myocardial cGMP levels, i.e., heart failure with preserved ejection fraction, remain to be investigated.

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